超温报警器 毕业设计

西安航空职业技术学院

毕业设计（论文）

论文题目：

所属学院：电子工程学院

指导老师：职称：

学生姓名：班级、学号:

专业：

西安航空职业技术学院制

年月日

西安航空职业技术学院

毕业设计（论文）任务书

题目：超温报警电路

任务与要求：

时间： 2014 年 11月24 日至 2015 年 1 月 16 日共 8 周所属学院：电子工程学院

学生姓名：学号：

专业：

指导单位或教研室：

指导教师：职称：

西安航空职业技术学院制

年月日

毕业设计(论文)进度计划表

本表作评定学生平时成绩的依据之一。

超温报警电路

【摘要】

随着科学技术的发展，人类对自动控制线路的开发不断深入，对各种控制线路的保护意识也逐渐增强。其中的超温报警电路是在实际应用中相当广泛的安全保护电路。所有电路均按基本功能分类编排，包括车辆类报警、有害气体类报警、无线遥控类报警、定时提醒类报警、设备故障类报警、电话自动类报警、电源安全及其他类报警应用电路。这些电路既有简单易制的家用防盗报警器电路，也有电路复杂的多功能报警器电路。在现实生活中，常有一种工程技术，即自动温度补偿的设备，在规定温度内正常工作，设备温度一旦超出上限，便立即切断电源报警。本次设计主要运用基本的模拟电子技术基础和传感器原理的知识，从基本的元器件出发，实现了超温报警电路的设计。超温报警电路是采用LM324温度传感器设计的，报警温度超过设定温度时会发出光报警信号。本电路主要由低功耗四运算放大器LM324、热敏电阻、LED发光二极管等元器件组成，并利用热敏电阻的阻值随着温度的升高而增大这个原理改变四运算放大器LM324比较器的比较电压，使其输出产生变化，从而引起发光二极管发出可见光，从而起到温度指示的作用。在实际应用中，利用发光二极管的温度指示作用来判断环境温度的变化，从而减少不必要的损失。

关键词：超温报警、热敏电阻、自动控制原理

Over temperature alarm circuit

Abstract:

With the development of science and technology, human beings to in-depth development of the automatic control circuit, gradually enhance the protection awareness of various control circuit. Over temperature alarm circuit which is a safety protection circuit is quite widespread in practical application. All circuits are basic function according to classification arrangement, including vehicle alarm, harmful gas alarm, wireless remote control alarm, timing prompt alarm, fault alarm, automatic equipment class class telephone alarm, power supply safety and other types of alarm application circuit. These circuits are both home burglar alarm circuit is simple and easy to make, also have multifunctional alarm circuit complex. In real life, often have a kind of engineering technique, namely, automatic temperature compensation equipment at the prescribed temperature in the normal work, equipment temperature once beyond the limit, immediately cut off the power supply alarm. The design of the main use of analog electronic technology and sensor principle of basic knowledge, starting from the basic components, the realization of the circuit design of alarm over temperature. Over temperature alarm circuit is designed using LM324 temperature sensor, the alarm will be issued when the temperature exceeds the set temperature and light alarm signal. The circuit is mainly composed of a low power four LM324 operational amplifier, a thermistor and the LED light emitting diodes and other components, and the use of the resistance of the thermistor comparison voltage increases with the temperature change of the principle of the four operational amplifier LM324 comparator, the output changes, thus causes the light emitting diode emits visible light, thus plays the temperature indicator the role of. In practical application, indicative function to judge the change of environment temperature using light emitting diode temperature, thereby reducing unnecessary losses. Key words:Over temperature alarm, automatic control theory, thermal resistance